/* 响应式样式 */
@media (max-width: 768px) {
    .sidebar {
        width: 200px;
    }
    
    .stats-container {
        flex-direction: column;
        gap: 12px;
    }
    
    .content-header {
        padding: 16px 20px;
    }
    
    .add-task-container,
    .tasks-container {
        padding: 0 20px;
    }
}